This invention relates to an information recording member which makes it possible to record on a real time basis frequency-modulated analog signals such as video and audio signals or digital data such as computer data, facsimile signals, digital audio signals, and the like, on an information recording film formed on a predetermined substrate, using recording beam such as laser light.
Various principles exist for recording information on a film using laser light. Among them, information recording based upon the change of atomic arrangement such as the phase transition (or phase change) of a film material, photodarkening, and the like, has the advantage that two discs can be directly bonded to form a two-surface disc because deformation of the film hardly occurs. Moreover, rewrite of the information can also be made by selecting a suitable composition. A large number of inventions relating to the recording of this kind are known, and the earliest of all is disclosed in U.S. Pat. No. 3,530,441. This prior art reference discloses a large number of films such as a Te--Ge film, an As--Te--Ge film, a Te--O film, and so forth. Japanese Patent Laid-Open No. 28530/1980 discloses Te--O--Se and Te--O--S films. However, it is extremely difficult to produce the films using these materials, and stability under the amorphous state is not sufficiently high.